#include<stdio.h>

int main()
{
	int num = 0,count = 0;
	printf("input a number :\n");
	scanf("%d",&num);

	/*while(num){
		if(num % 10 == 0){
			count ++;
		}
		num /= 10;
	}*/

	do
	{
		if(num % 10 == 0){
			count ++;
		}
		num /= 10;
	}while(num);

	
	printf("count = %d\n",count);
		
	return 0;
}
